322 PHILOSOPHICAL TRANSACTIONS. [aNNO iSsG. 



petual, viz. all along the coast of Guinea for above 5CX) leagues together, from 

 Sierra Leona to the isle of St. Thomas ; for the south east trade wind having 

 passed the line, and approaching the coast of Guinea within 80 or 100 leagues 

 inclines towards the shore, and becomes S S. E. and by degrees, as you come 

 nearer, it veers about to south, S. S. W. and in with the land south-west, and 

 sometimes W. S.W. These are the winds which are observed on this coast, 

 when it blows true ; but there are frequent calms, violent sudden gusts, called 

 tornadoes, from all points of the compass, and sometimes unwholesome foggy 

 easterly winds, called hermitan by the natives, which too often infest the navi- 

 gation of these parts. 



7. That to the northward of the line between 4 and 10° of latitude, and be- 

 tween the meridians of Cape Verde, and of the easternmost islands that bear that 

 name, there is a tract of sea wherein it were improper to say there is any trade 

 wind, or yet a variable one ; for it seems condemned to perpetual calms, attended 

 with terrible thunder and lightning, and rains so frequent, that our navigators 

 from thence call this part of the sea the Rains; the little winds they have are 

 only some sudden uncertain gusts, of very short continuance, and less extent ; 

 so that sometimes each hour there is a different gale, which dies away into a 

 calm before another succeeds ; and in a fleet of ships, in sight of one another^ 

 each will have the wind from a different point of the compass ; with these weak 

 breezes ships are obliged to make the best of their way to the southward, through 

 the aforesaid 6°, wherein it is reported some have been detained whole months 

 for want of wind. 



From the last three observations is shown the reason of two notable occur- 

 rences in the East India and Guinea navigations. The one is, why, notwith- 

 standing the narrowest part of the sea between Guinea and Brasil is about 500 

 leagues over, yet ships bound to the southward, especially in the months of 

 July and August, find sometimes a great difficulty to pass it. This happens 

 because of the south-east winds at that time of the year commonly extending 

 some degrees beyond the ordinary limit of 4° north latitude, and coming also so 

 much southerly as to be sometimes south, sometimes a pointer two to the west; 

 there remains then only to ply to windward ; and if on the one side they stand 

 away W. S.W. they gain the wind still more and more easterly ; but there is 

 danger of not weathering the Brasilian shore, or at least the shoals on that coast. 

 But if, on the other tack, they go away E. S. E. they fall into the neighbourhood 

 of the coast of Guinea, from which there is no departing, without running 

 easterly, as far as the isle of St. Thomas, which is the constant practice of all 

 the Guinea ships, and which may seem very strange without considering the 

 sixth remaHi, which shows the reason of it. For being in with the coast the 



